i wish i knew the answer. lol! i can't always get my 3 year old to take a nap...and then he too is grumpy, but he'll go to bed REALLY well at night. for now, i have decided, for myself and my sanity, i prefer for him to take the nap, and then stay up a wee bit later as a happier child with a happier mom. i try to give him a nap pretty early, like lunch at 11, followed by nap, bedtime between 6:30-7. definitely more like 7 if he has napped, more like 6:30 if he did not. at first we were having a hard time getting him to stay in bed at all, which meant it was taking a LONG time for him to fall asleep, but we put up a behavior chart with 8 squares. he earns one square for each night he stays in bed and goes to sleep, when all the squares are filled, he gets a hotwheel car. i can not tell you how successful this has been. now he stays in bed, which means he is falling asleep pretty quickly once we lay him down. don't ask "why 8 squares?" it was just how many were on the page. lol! i just google "free behavior charts" and then download a new one each time we start over. he LOVES it! and i am happier too. ")